Comment by anotherman554

Apparently Mark Twain never said it.

If the quote stated "If you are ignorant on a topic it's better not to discuss it" that would be advise. (Though less quippy).

But I read the quote as essentially saying:

"You are so incredibly stupid you should never, ever attempt to speak to another human being ever again, on any conceivable subject".

But maybe some people don't take it that way.